Month: August 2021

Related Products of 76537-18-3, These common heterocyclic compound, 76537-18-3, name is 3-Bromo-5-chloropyrazin-2-amine, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.

First, into a three-neck flask equipped with a reflux pipe were put 5.01 g of 60 3-bromo-5-chloropyrazin-2-amine, 6.04 g of 5 2-methoxynaphthalene-1-boronic acid, 5.32 g of 6 potassium fluoride, and 86 mL of dehydrated tetrahydrofuran, and the air in the flask was replaced with nitrogen. The mixture in the flask was degassed by being stirred under reduced pressure, and then 0.44 g of 7 tris(dibenzylideneacetone)dipalladium(0) (abbreviation: Pd2(dba)3) and 3.4 mL of 8 tri-tert-butylphosphine (abbreviation: P(tBu)3) were added thereto. The mixture was stirred at 80 C. for 22 hours to be reacted. After a predetermined time elapsed, the obtained mixture was subjected to suction filtration and the filtrate was concentrated. Then, purification by silica gel column chromatography using a developing solvent (toluene:ethyl acetate=10:1) was performed, so that 5.69 g of a target pyrazine derivative (yellowish white 61 powder) was obtained in a yield of 83%. A synthesis scheme of Step 1 is shown in (e-1) below

Statistics shows that 3-Bromo-5-chloropyrazin-2-amine is playing an increasingly important role. we look forward to future research findings about 76537-18-3.

Reference:
Patent; Semiconductor Energy Laboratory Co., Ltd.; Yamaguchi, Tomoya; Yoshizumi, Hideko; Kido, Hiromitsu; Seo, Satoshi; Sasaki, Toshiki; (180 pag.)US2019/31673; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 22047-25-2, name is Acetylpyrazine, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route. category: Pyrazines

General procedure: A 2-neck round bottom flask attached with calcium chloride guard tube was charged with MeOH (30mL). Then, 2-acetylpyrazine (1.47g, 2mmol) followed by KOH pellets (0.675g, 2mmol) were added and initiated magnetic stirring. To this mixture, distilled water (2mL) was added and continued stirring for 10min. Now, the resulting solution was added the respective n,n?,n?-trimethoxyphenyl benzaldehydes (1.0g, 1mmol) under stirring at room temperature slowly and then 6mL of ammonia solution was added. The reaction mixture was stirred further for 4h. The reaction was monitored by TLC. On completion of reaction by TLC, the reaction mass was filtered and washed with methanol (3×10 mL) and then diethyl ether (3×10 mL) to obtain a white precipitate of respective compounds. Each of the above precipitates was recrystallised in a mixture of CHCl3 and MeOH (1:1) at room temperature for 48h. The resulting colourless single crystals of 1-3 were collected by filtration.

The synthetic route of Acetylpyrazine has been constantly updated, and we look forward to future research findings.

Reference:
Article; Ramesh; Sharath Kumar; Raghavendra Kumar; Suchetan; Devaraja; Sabine, Foro; Nagaraju; Journal of Molecular Structure; vol. 1200; (2020);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, A new synthetic method of this compound is introduced below., HPLC of Formula: C4H3Br2N3

3,5-Dibromopyrazin-2-amine (200 mg, 0.79 mmol) and chloroacetaldehyde (200 mul, 1.58 mmol) were dissolved in DMF (5 ml). The mixture was stirred at 100 C. overnight. LC/MS showed 6,8-dibromoimidazo[1,2-a]pyrazine plus the mass with one bromine displaced by chlorine. The crude material was used for the next step without further purification. 1H NMR (400 MHz, CDCl3) delta 8.28 (s, 1H) 7.88 (s, 1H) 7.80 (s, 1H). [M+H] calc’d for C6H3Br2N3, 276; found, 276.

The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.

Reference:
Patent; Dong, Qing; Hosfield, David J.; Paraselli, Bheema R.; Scorah, Nicholas; Stafford, Jeffrey A.; Wallace, Michael B.; Zhang, Zhiyuan; US2006/84650; (2006); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 6164-79-0, In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 6164-79-0, name is Methyl 2-pyrazinecarboxylate belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

[0537] Synthesis of pyrazin-2-ylmethanol: [0538] To a stirred solution of methyl pyrazine-2-carboxylate (0.5 g, 3.62 mmol) in H20 (10 mL) was added NaBH4 (685 g, 18.02 mmol) portion wise at 0 C, and the reaction mixture was allowed to warm to RT and stirred for 30 min under inert atmosphere. To this saturated K2C03 (10 mL) and EtOH (5 mL) was added and stirring was continued for another 1 h at RT. The progress of the reaction was monitored by TLC; the reaction mixture was extracted with EtOAc. The combined organic layer was dried over sodium sulphate, filtered and concentrated in vacuo to afford crude pyrazin-2-ylmethanol (0.3 g). LC-MS: 99.91%; 111.9 (M++l) (column; X-bridge C-18, (50×3.0 mm, 3.5mu); RT 0.72 min. 0.1% TFA in water: ACN; 0.8 ml/min); TLC: 100% EtOAc (Rf: 0.2).

The synthetic route of Methyl 2-pyrazinecarboxylate has been constantly updated, and we look forward to future research findings.

Reference:
Patent; ENVIVO PHARMACEUTICALS, INC.; RIPKA, Amy; SHAPIRO, Gideon; MCRINER, Andrew, J.; BURSAVICH, Matthew, Gregory; WO2013/142269; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 143591-61-1, Each compound has different characteristics, and only by selecting the characteristics of the compound suitable for a specific situation can the compound be applied on a large scale. 143591-61-1, name is 3-Bromo-8-chloroimidazo[1,2-a]pyrazine, This compound has unique chemical properties. The synthetic route is as follows.

Intermediate Example 7-1 : Preparation of 3-bromo-N-(2- methylpropyl)imidazo[ 1 ,2-a]pyrazin-8-amineTo a stirred solution of 3-bromo-8-chloro-imidazo[1 ,2-a]pyrazine which was prepared according to intermediate example 2-1 (4 g, 17.2 mmol) in THF (54 mL) was added 4.9 mL isobutylamine (3.77 g, 51.6 mmol, 3 eq) and 7.2 mL TEA (5.22 g, 51.6 mmol, 3 eq) in one portion at rt and the mixture was heated at 140C in a microwave tube. Purification by flash chromatography yielded 4.45 g (91 %) of the title compound. 1H-NMR (300 MHz, d6-DMSO): delta = 7.64 (d, 1 H), 7.61 (s, 1 H), 7.48 (d, 1 H), 7.36 (d, 1 H), 3.24 (dd, 2H), 1.96 (m, 1 H), 0.85 (d, 6H) ppm. UPLC-MS: RT = 0.84 min; m/z 270.2 [MH+]; required MW = 269.2.

The chemical industry reduces the impact on the environment during synthesis 3-Bromo-8-chloroimidazo[1,2-a]pyrazine. I believe this compound will play a more active role in future production and life.

Reference:
Patent; BAYER PHARMA AKTIENGESELLSCHAFT; KOPPITZ, Marcus; KLAR, Ulrich; JAUTELAT, Rolf; KOSEMUND, Dirk; BOHLMANN, Rolf; BADER, Benjamin; LIENAU, Philip; SIEMEISTER, Gerhard; WO2012/80229; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 13924-94-2, In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 13924-94-2, name is Methyl 5-aminopyrazine-2-carboxylate belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

Methyl 5-aminopyrazine-2-carboxylate (8) (0.650g, 4.2483mmol) was reacted with excess of acetic anhydride (5mL) and heated at 90C for 2h. The reaction mixture was evaporated and partitioned between saturated NaHCO3 solution and ethyl acetate. Organic layer was evaporated to get 0.345g of compound 9a as pale yellow solid (yield 41.6%). 1H NMR (400MHz, DMSO-d6) delta 11.29 (s, 1H), 9.41 (d, J=1.4Hz, 1H), 8.96 (d, J=1.4Hz, 1H), 2.18 (s, 3H), 1.81 (s, 3H). C8H9N3O3 [M]: 195.18; MS (ESI) m/z: [M+H]+: 196.05 [M-H]+, 194.05

In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, Methyl 5-aminopyrazine-2-carboxylate, other downstream synthetic routes, hurry up and to see.

Reference:
Article; Trivedi, Prakruti; Adhikari, Nilanjan; Amin, Sk. Abdul; Jha, Tarun; Ghosh, Balaram; European Journal of Pharmaceutical Sciences; vol. 124; (2018); p. 165 – 181;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

117719-17-2, name is 5-Bromo-3-morpholinopyrazin-2-amine, belongs to pyrazines compound, is considered to be a conventional heterocyclic compound, which is widely used in drug synthesis. The chemical synthesis route is as follows. name: 5-Bromo-3-morpholinopyrazin-2-amine

Chloroacetaldehyde (4.4 g) was mixed with isopropanol (15 mL) and a portion of the mixture (10 mL) was added to a round bottom flask containing compound 2 (1.7 g). Then the temperature was raised to 45 C and stirring was continued. After 1 h, the remaining solution was added and thetemperature raised to 65 C with continuous stirring. After TLC indicated the reaction was finished, the reaction was stopped and cooled to room temperature. Then the solution was added into a beaker containing ice water (300 mL) with continuous stirring. The brown-yellow solid that precipitated was filtered and dried to give the product in a yield of 26.8%. 1H-NMR (DMSO-d6) delta 7.93 (s, 1H),7.25 (d, J = 7.3 Hz, 1H), 7.01 (d, J = 7.3 Hz, 1H), 3.45 (s, 4H), 3.77 (d, J = 4.3 Hz, 4H).

The synthetic route of 117719-17-2 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Xu, Shan; Sun, Chengyu; Chen, Chen; Zheng, Pengwu; Zhou, Yong; Zhou, Hongying; Zhu, Wufu; Molecules; vol. 22; 2; (2017);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

875781-43-4, name is 2-Bromo-5H-pyrrolo[2,3-b]pyrazine, belongs to pyrazines compound, is considered to be a conventional heterocyclic compound, which is widely used in drug synthesis. The chemical synthesis route is as follows. HPLC of Formula: C6H4BrN3

To a solution of I-69 (300 mg, 0.6 mmol) in DMF (10 mL) are added I-87 (140 mg, 0.7 mmol), tetrakis(triphenylphosphine)palladium (0) (70 mg, 0.06 mmol) and 2M Na2CO3 (1.5 mL, 3.0 mmol). The mixture is heated to 100 C. for 1 hour in a microwave reactor. The mixture is cooled down and is extracted with H2O (20 mL) and EtOAc (30 mL). The combined organic layer is dried with MgSO4 and is filtered. The filtrate is concentrated and the residue is purified by silica gel flash column chromatography with 10% MeOH in CH2Cl2 as the eluent to afford the title compound (200 mg). Example 176-180, Table 1-the reaction is run at 120 C.Example 176-180, Table 1-the reaction is run at 120 C. [0509] Example 184-185, Table 1-the reaction is run at 120 C Example 191, Table 1-the reaction is run at 120 C. Example 239-243, Table 1-the reaction is run for 6 hours at 100 C. in an oil bath

The synthetic route of 875781-43-4 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Boehringer Ingelheim International GmbH; BYLOCK, Lars Anders; US2013/195879; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Some common heterocyclic compound, 109838-85-9, name is (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine, molecular formula is C9H16N2O2, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route. name: (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine

To a 500 mL flame dried flask was added (i?)-2-isopropyl-3, 6- dimethoxy-2,5-dihydropyrazine (10.0 g, 54.3 mmol) and anhydrous THF (200 mL). The solution was cooled to -78 °C. “-BuLi (2.5M in hexane, 24.0 mL, 59.7 mmol) was added dropwise. After the solution was allowed to stir at -78 °C for 30 minutes, Compound Int-16b (in 5 mL anhydrous THF) was added dropwise. After the solution was allowed to stir at -78 °C for 1 hour, it was allowed to warm up to room temperature in two hours. Water (100 mL) and Et20 (150 mL) were added. The organic layer was separated and the aqueous layer was extracted with Et20 (100 mL) twice. The organic layers were combined, washed with brine, dried over Na2S04, filtered and concentrated in vacuo. The residue obtained was purified using Si02 chromatography (40 g, eluted with Et20 in Hexane: 0percent to 3percent) to provide Compound Int-16c (10.43 g, 58.0percent).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 109838-85-9, its application will become more common.

Reference:
Patent; MERCK SHARP & DOHME CORP.; KOZLOWSKI, Joseph A.; ROSENBLUM, Stuart B.; COBURN, Craig A.; SHANKAR, Bandarpalle, B.; ANILKUMAR, G., Nair; CHEN, Lei; DWYER, Michael, P.; JIANG, Yueheng; KEERTIKAR, Kartik, M.; LAVEY, Brian, J.; SELYUTIN, Oleg, B.; TONG, Ling; WONG, Michael; YANG, De-Yi; YU, Wensheng; ZHOU, Guowei; WU, Hao; HU, Bin; ZHONG, Bin; SUN, Fei; JI, Tao; SHEN, Changmao; RIZVI, Razia; ZENG, Qingbei; WO2012/41014; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 1379338-74-5, The chemical industry reduces the impact on the environment during synthesis 1379338-74-5, name is 5,7-Dichloropyrido[3,4-b]pyrazine, I believe this compound will play a more active role in future production and life.

Intermediate 22: 1,1-Dimethylethyl (2R)-2-{[(7-chloropyrido[3,4-b]pyrazin-5-yl)amino]methyl}-4-morpholinecarboxylate 1,1-dimethylethyl (2R)-2-(aminomethyl)-4-morpholinecarboxylate (for preparation see: J. Medicinal Chemistry, 2009, 52 (15), 4810-4819) (6 g, 27.7 mmol) was dissolved in N-methyl-2-pyrrolidinone (NMP) (60 mL) and to this was added DIPEA (7.27 mL, 41.6 mmol) and 5,7-dichloropyrido[3,4-b]pyrazine (5.55 g, 27.7 mmol). This was split between 4 large microwave vials and each was heated at 130 C. for 30 min. They were monitored by LCMS and were given a further 10 min at 130 C. The reaction mixtures were partitioned between ethyl acetate (700 ml) and diluted aqueous ammonium chloride (1 litre). The aqueous was reextracted with ethyl acetate (300 ml) and the combined organics were washed with aqueous ammonium chloride (500 ml), dried over sodium sulfate and concentrated in vacuo to yield a crude brown oil. It was dissolved in DCM and passed through silica (70 g) eluting with DCM (6*40 ml) then 5% ethyl acetate in DCM (2*40 ml), 10% ethyl acetate in DCM (5*40 ml) then 15% ethyl acetate in DCM (2*40 ml) then 20% ethyl acetate in DCM (2*40 ml). Appropriate fractions were combined and concentrated in vacuo to yield: N8231-100-2, orange-yellow slightly gummy solid, 7.7 g LCMS (Method B): Rt=1.17 min, MH+ 380

In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, 5,7-Dichloropyrido[3,4-b]pyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; GLAXO GROUP LIMITED; Atkinson, Francis Louis; Atkinson, Stephen John; Barker, Michael David; Douault, Clement; Garton, Neil Stuart; Liddle, John; Patel, Vipulkumar Kantibhai; Preston, Alexander G.; Shipley, Tracy Jane; Wilson, David Matthew; Watson, Robert J.; US2014/5188; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem